Grayscale printing, in general, enables a user to select a “grayscale” only print option to enable all print job content to render into grayscale. Currently, all object color types, when grayscale printing is selected, are routed through appropriate print paths to achieve the grayscale. Object data content can be red, green and blue (RGB) color, cyan, magenta, yellow and key (CMYK), spot color, and the like and the object type can be images, text, graphic objects and the like.
Some printers use an International Color Consortium (ICC) profile. The ICC profile offers “compression” of tone from the RGB color space to the print space to accommodate the print space's inability to realize an L* (in a CIE lab color space L, a, b) lightness value of zero. This compression tone enables the printing of “shadow detail” viewable on a monitor, but, not physically realizable in print.
In addition, most of the compression from the L, a, b color space is converted into a CMYK color space where C, M and Y still have values. Thus, this is not true grayscale printing.